This information is part of the Modelica Standard Library maintained by the Modelica Association.
Basic model for Coulomb friction that models the stuck phase in a reliable way.
This procedure is implemented in a "clean" way by state events and leads to a mixed continuous/discrete systems of equations if friction elements are dynamically coupled which have to be solved by appropriate numerical methods. The method is described in (see also a short sketch in UsersGuide.ModelingOfFriction):
Type: Velocity (m/s)
Description: Relative velocity near to zero (see model info text)